WSDualHttpBinding binding = new WSDualHttpBinding();
binding.Security.Mode = WSDualHttpSecurityMode.None;
binding.Security.Message.ClientCredentialType = MessageCredentialType.None;
binding.ProxyAddress = new Uri("http://proxyName:3333");
binding.UseDefaultWebProxy = false;
                
InstanceContext context = new InstanceContext(this);
DuplexChannelFactory<IUserService> factory = new DuplexChannelFactory<IUserService>
                                                                (context
                                                                 ,binding
                                                                 ,string.Format("{0}/{1}"
                                                                 ,baseAddres
                                                                 ,typeof(IUserService).Name)
                        );
                
                factory.Credentials.UserName.UserName = "user";
                factory.Credentials.UserName.Password = "p@$$word";